The Portfolio Diet is a scientifically validated, plant-based dietary approach that integrates soluble fiber, plant sterols, ...

This tool has been validated in a large independent cohort and has been shown to have a high content validity, to be highly reproducible and to be able to detect change.3,4 In the past few years, the ...

Method: A systematic literature review was undertaken to study sample and questionnaire design characteristics (source, no of items, scale type), construct validity (content validity, factor structure ...